Safety of estrogen ring on Arimidex?

Question fromSalH:
I am on Arimidex and find intercourse extremely painful due to dryness. How safe is the estrogen ring?

Answers -Patricia A. Ganz, M.D.
Using vaginal estrogen even in low dose may complicate the management of your treatment on Arimidex. We have felt comfortable using vaginal estrogen supplements such as Vagifem or Estring for women who are on tamoxifen because tamoxifen blocks the uptake of any blood level of estrogen that could get into breast cancer cells. However, the strategy of using Arimidex and the other aromatase inhibitors is to lower the estrogen level as low as possible, down to nearly zero. If you use a vaginal estrogen preparation, even in these low doses, it will raise the estrogen level in the blood so that you may be counteracting the benefits of the aromatase inhibitor. I am currently measuring estradiol blood levels in my patients who are using vaginal estrogen because I want to make sure it doesn't elevate the levels. So you might be defeating the purpose of the aromatase inhibitor. If this were to be used, it would have to be used with great caution and with monitoring. You can also use other non-estrogen preparations. One is Replens, a vaginal moisturizer used twice a week. In a randomized trial that we did several years ago, we found that women's vaginal symptoms improved and their sexual functioning also improved. You can also use a preparation as a lubricant at the time of sexual intercourse, which may also help, and there is a variety available at the drug store. You should also know that vaginal dryness is a common symptom of women as they age, so what you are experiencing is an exaggeration of the symptoms that women in postmenopausal years experience.

The Ask-the-Expert Online Conference called Managing Ongoing Medications featured Patricia Ganz, M.D. and moderator Lillie Shockney, R.N., B.S., M.A.S. answering your questions about staying on track with breast cancer medications you have to take on a regular basis.

Editor's Note: This conference took place in August 2007.

The materials presented in these conferences do not necessarily reflect the views of Breastcancer.org. A qualified healthcare professional should be consulted before using any therapeutic product or regimen discussed. All readers should verify all information and data before employing any therapies described here.